People line up to to get medical attention in La Gloria, Mexico. Mexico's Health Secretary Jose Angel Cordova downplayed claims Tuesday that the swine flu epidemic could have started in La Gloria, noting that of 35 mucous samples taken from respiratory patients there, only one has came back positive, even though in March about 450 people were diagnosed with acute respiratory infections and sent home with antibiotics and surgical masks.

Bertha Crisóstomo, a community leader and activist, says many people in the village fell ill with similar symptoms around 21 March. Like many people in the village, she suspects that the industrial pig farms in the area, known as Granjas Carroll and owned by the Virginia-based company Smithfield, may be to blame

An employee works on a farm run by Granjas Carroll de Mexico on the outskirts of Xicaltepec in Mexico's Veracruz state. Mexico's agriculture department said on Monday that its inspectors found no sign of swine flu among pigs around the farm in Veracruz and no infected pigs have been found anywhere in Mexico

Granjas Carroll of Mexico, in Perote, Veracruz, Mexico. Veratect Corporation, a US biosurveillance consultancy firm, said they identified the first case of swine flu virus on 2 April in the Mexican town of Perote in Veracruz